Sheet package

ABSTRACT

This disclosure provides a sheet package which prevents sheets taken out from the sheet package from being inserted into the sheet package again and which also prevents sheets from dropping out of the sheet package. The sheet package is made up of a package material folded into a rectangular parallelepiped thin box. Ear portions which serve as a sheet intrusion blocking member are located in a space sandwiched by a bottom face and a first sheath portion and side ends of the ear portions make contact with end portions of sheets in an insertion direction so that the end portions of the sheets cannot reach a side wall portion. Thus, the sheets cannot be restored to their original storage positions in the sheet package completely and part of the sheets project from the sheet package. Thus, dropped sheets cannot be restored to the sheet package through an opening portion, and sheets to which either dust or dirt has adhered are thus prevented from being reused.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from JP2006-338833, filed on Dec. 15,2006 and JP 2007-309189 filed on Nov. 29, 2007, the entire disclosure ofwhich is incorporated herein by reference there.

BACKGROUND

The present disclosure relates to a sheet package. More particularly toa sheet package that protects the outside of a stack of sheets with itspackage member and that can be set in a printer unit together with apackage material.

Conventionally, there has been known a sheet package which accommodatesa stack of sheets in its box-like package member and which, when thesheets are used for printing can be set in a printer unit by opening thelid portion of the package member and by folding it back to the oppositeside (see, for example, Japanese Patent Application Publication No.2003-285939). Because this sheet package can handle a plurality ofsheets in units of a package, convenience of usage thereof is improved.And because the package member can protect sheets inside by covering,this sheet package is effective in adopting heat sensitive sheets thatare susceptible to light or heat as paper sheets for the printer unit.

SUMMARY

However, in the case of a conventional sheet package, when at a time ofusage a part of the sheets is exposed, as a result of the opening of thelid portion, sometimes sheets stored inside the sheet package can dropout of the sheet package. In such circumstances, if printing is executedby setting a sheet package in which the dropped sheets are insertedbecause the dropped sheets can be brought back into the sheet packageeasily through an opening portion, impurities such as dust and dirtwhich adhere to the sheet have tended to damage a printing head of theprinter unit.

Further, because the conventional sheet package has no pressing meansfor supporting sheets contained in the interior, when the openingportion of a sheet package is directed in a downward direction duringthe handling of a sheet package, sheets can drop out.

The present disclosure has been accomplished to solve theabove-described problems and a first object of the disclosure is toprevent sheets taken out from the sheet package temporarily from beinginserted back into their original storage position within the sheetpackage. Further, a second object of the disclosure is to achieve asheet package out of which sheets never drop.

In order to achieve the above-described objects, according to an aspectof the present disclosure, there is provided a sheet package comprising:sheets that are accommodated in the sheet package, as printing objectmediums for a printer unit and a package material that covers the outersides of the stacked sheets and having; a first portion that isrectangular and covers a surface on one side in a stacking direction ofthe stacked sheets; a second portion that covers a surface on anotherside in a stacking direction of the stacked sheets opposite to the firstportion; a third portion that is connected to both the first portion andto the second portion for covering a side face of the stacked sheets inparallel to a conveyance direction of the sheets; a fourth portion thatcovers the side face of the stacked sheets in parallel to the conveyancedirection of the sheets and that is opposite to the third portion acrossthe stacked sheets; a fifth portion that is connected to the firstportion or the second portion and that covers the side face of thestacked sheets on an upstream side in the conveyance direction of thesheets; an opening portion that exposes part of the sheets from thepackage material; and sheet intrusion blocking members that prevent thesheets discharged through the opening portion from being inserted onceagain through the opening portion and pressed against their originalstorage positions, the sheet intrusion blocking members being providedin the interior after assembly of the sheet package, wherein the sheetpackage being structured so as to be capable of being set in the printerunit together with the package material with part of the sheets exposed.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the disclosure will be described below indetail with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a printer unit;

FIG. 2 is a sectional view taken along the line I-I in FIG. 1;

FIG. 3 is a diagram showing a condition in which a sheet package is setin a sheet storage portion;

FIG. 4 is an enlarged sectional view showing the details of asheet-separating portion and a printing mechanism portion;

FIG. 5 is a perspective view of the sheet package;

FIG. 6 is a perspective view of a sheet package with the lid portionfolded back to the rear side;

FIG. 7 is a bottom face view of the sheet package;

FIG. 8 is an exploded view of the package according to a firstembodiment as seen from the exterior;

FIG. 9 is a perspective view of an exploded condition as seen from theinterior of the package member;

FIG. 10 is a perspective view showing a process of manufacturing thesheet package;

FIG. 11 is a perspective view showing a process of manufacturing thesheet package;

FIG. 12 is a perspective view showing a process of manufacturing thesheet package;

FIG. 13 is a perspective view showing a process of manufacturing thesheet package;

FIG. 14 is a perspective view showing a process of manufacturing thesheet package;

FIG. 15 is a perspective view showing an opening action at a time that asheet package is used;

FIG. 16 is a perspective view showing an opening action at a time that asheet package is used;

FIG. 17 is a side view diagram showing a loading action of loading thesheet package to a printer unit;

FIG. 18 is a sectional view taken along the line III-III in FIG. 16 ofthe sheet package;

FIG. 19 is a sectional view taken along the line III-III of the sheetpackage in FIG. 16 when sheets are consumed so that the quantity of theaccommodated sheets is decreased;

FIG. 20 is a sectional view taken along the line III-III of the sheetpackage in FIG. 16 when no sheet exists in the interior;

FIG. 21 is a perspective view showing a condition in which sheets areinserted into the sheet package;

FIG. 22 is a longitudinal sectional view of a sheet package when thesheets are inserted through an opening portion in the sheet package;

FIG. 23 is an exploded view of a sheet package according to a secondembodiment as seen from the exterior of the package material;

FIG. 24 is a perspective view showing a halfway condition of assembly ofthe sheet package according to the second embodiment;

FIG. 25 is an exploded view of the sheet package according to a thirdembodiment as seen from the exterior of the package material; and

FIG. 26 is an exploded view of the sheet package according to a fourthembodiment as seen from the exterior of the package material.

FIG. 27 is an exploded view of the sheet package according to a fifthembodiment as seen from the interior of the package material.

FIG. 28 is a partial enlarged view of the sheet package according to asixth embodiment as seen from the interior of the package material.

FIG. 29 is a partial enlarged view of the sheet package according to aseventh embodiment as seen from the interior of the package material.

FIG. 30 is a pattern diagram of vertical sectional view of the fold lineprocessing adjacent to the bottom portion, side wall portion andboundary line of the sheet package according to a fifth embodiment ofthe conventional package material.

FIG. 31 is a pattern diagram of vertical sectional view of the fold lineprocessing adjacent to the bottom portion, side wall portion andboundary line of the sheet package according to a fifth embodiment ofthe package material.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, the structure of a printer unit on which a sheet package 9is to be loaded according to a first embodiment of the presentdisclosure will be described with reference to FIGS. 1-4.

As shown in FIG. 1, the printer unit 1 is formed into a flat typerectangular parallelpiped configuration approximately 2 cm in thickness,while its rectangular shape as seen in a plan view is slightly largerthan A6 size. A main body case 2 which constitutes a casing of theprinter unit 1 is comprised of a frame body 3, a lower cover 4, an uppercover 5, a lid body 10 and the like. The frame body 3 constitutes aframe of the printer unit 1, presenting a rectangular shape as seen inits plan view. The lower cover 4 covers the bottom face of the framebody 3, presenting a rectangular shape as seen in its plan view. Theupper cover 5 covers part of the top face of the frame body 3. The lidbody 10 is structured so as to be capable of being opened and closed.

As shown in FIGS. 2 and 3, a printing mechanism portion 14 isincorporated inside an end portion (upper side in FIGS. 2 and 3) of theprinter unit 1 and a rectangular top cover 5 as seen in its plan view isprovided in such a way as to cover its top face. A sheet storage portion6 is formed in the remaining portion of the top face of the frame body 3that excludes the portion covered by the top cover 5. The top of thesheet storage portion 6 is covered by a rectangular lid body 10 as seenin its plan view. The lid body 10 can be opened and closed freely asshown in FIG. 2.

The sheet storage portion 6 can accommodate a sheet package 9 in which aplurality of sheets 7, for example A6 or A7 sized cut-sheet type heatsensitive papers, can be stored inside a package material 8, as shown inFIG. 3. The main body case 2 is equipped with a locking mechanism (notshown), and when a sheet package 9 set in the sheet storage portion 6, alid body 10 can be closed and locked as shown in FIG. 3.

A pickup roller 12, a separation block 13 and the like are disposed as asheet-separating portion 11 at an end portion on the printing mechanismportion 14 side of the sheet storage portion 6. A thermal head 15, aplaten roller 16 and a paper guide 17 are disposed as a printingmechanism portion 14 below the top cover 5.

The paper separation portion 11 will next be described with reference toFIG. 4. As shown in FIG. 4, the pickup roller 12 and the separationblock 13 are provided at an end portion on a side close to the printingmechanism portion 14 of the sheet storage portion 6. At such an innerface of the lid body 10 as to face the sheet storage portion 6, apressing plate 18 is supported in condition where it can swing. Acoil-like urging spring 19 is interposed between the pressing plate 18and the lid body 10 so as to apply constantly to the pressing plate 18an urging force in a direction of the rotation of the pressing plate 18in a downward direction.

The sheet package 9 is loaded on to the sheet storage portion 6 with abottom face of a sheet located on the bottommost position of sheets 7stored in the sheet package 9 in a stacked condition with the printingobject faces of the sheets 7 directed in a downward direction, and in astate in which they are exposed partly from the package material 8.Then, when the lid body 10 is closed and locked, the pressing plate 18urged by an urging spring 19 in a downward direction presses the exposedportion of the sheet 7 against the pickup roller 12 through the packagematerial 8 so that the bottom face of the sheet 7 is brought intocontact with the pickup roller 12.

As shown in FIG. 4, the separation block 13 which constitutes thesheet-separating portion 11 is provided such that it is located in thevicinity of and opposes the pickup roller 12. The separation block 13has a separation guide face 13 a which is inclined with respect to adirection of feeding sheets by the pickup roller 12. In asheet-separating portion 11 having such a structure, the pickup roller12 is driven so that a frictional transportation force is applied to thesheet 7 that is located on the bottommost layer and that is in contactwith the pickup roller 12. Then, only the sheet 7 located on thebottommost layer is separated and fed by the separating action of theseparation guide face 13 a of the separation block 13 in tandem with thefrictional transportation force.

Next, the printing mechanism portion 14 will be described. As shown inFIG. 4, the platen roller 16 is provided being driven rotatably by amotor (not shown) on the opposite side to the pickup roller 12 acrossthe separation block 13, and a paper guide 17 is disposed in thevicinity of the outer peripheral face of the platen roller 16. The paperguide 17 has a concavely curved sliding contact face 17 a that possessesa substantially U-shaped section as seen in a lateral direction, and thepaper guide 17 is provided so as to extend along the outer peripheralface of the cylindrical platen roller 16. A pressing coil spring 20 isprovided between the paper guide 17 and the main body case 2 so as tourge the sliding contact face 17 a toward the outer peripheral face ofthe platen roller 16.

In a printer unit 1 having such a structure, a sheet 7 separated by thesheet-separating portion 11 is conveyed by the pickup roller 12 andpasses between the bottom end of the separation block 13 and a guideplate 21 that guides the sheet in the direction of the platen roller 16.The sheet 7 is guided by the guide plate 21 and guided from the bottomside of the platen roller 16 to a portion between the platen roller 16and the paper guide 17. The sheet 7 is held between the outer peripheralface of the platen roller 16 and the sliding contact face 17 a of thepaper guide 17 and conveyed in a state in which it is inverted into a Ushape as seen in a lateral direction by a rotation of the platen roller16. The sheet accordingly reaches the top side of the platen roller 16with its printing object face facing an upward direction.

As shown in FIG. 4, a thermal head 15 that is located above the platenroller 16 has a heat-generating body portion 15 a. The thermal head 15is provided rotatably around a rotation shaft 15 b, and the heatgenerating portion 15 a is configured in such a way as to be capable ofmaking contact with, and moving away from, the top face of the platenroller 16. The reason why the thermal head 15 is configured in such away as to be rotatable is that in removing a jammed paper when a sheet 7is jammed between the platen roller 16 and the paper guide 17, thethermal head 15 is in this way prevented from becoming an impediment tothat removal work.

As shown in FIG. 4, an end of a torsion coil spring type spring 22 isattached to the thermal head 15 so as to always apply an urging forceconstantly in a direction in which the heat-generating body portion 15 aof the thermal head 15 is made to approach the top face of the platenroller 16. With this configuration, the heat-generating body portion 15a of the thermal head 15 makes contact with the top face of a sheet 7conveyed by the platen roller 16 with its printing object face directedin an upward direction and, the sheet 7 is then printed at the positionwhere contact is made.

The thermal head 15 is of a line head type and can accordingly print anycharacter or image on each individual line extending in a directionperpendicular to the conveyance direction of the sheet 7 on the conveyedheat sensitive type sheet 7. A printing width at the time that printingis performed on a single line is set so as to substantially equal to thewidth of the paper 7 which is a printing object. Because the thermalhead 15 is used as a printing head, a heat sensitive paper is used as aprinting object medium and thus, consumables such as ink and ink ribbonare reduced unnecessary. Further, a mechanism for supplying ink can becurtailed, thereby resulting in a compact structure of the printer unit1. As the heat sensitive paper, heat sensitive coloring type having acoloring layer which generates color when heated by the thermal head 15,and a heat sensitive boring type in which a boring layer is overlaid ona base material layer and in which, the boring layer being bored whenheated and other types are available.

A sheet discharge guide face 13 b, which is inclined with respect to asheet-feeding direction of the platen roller 16, is formed on theseparation block 13. With this structure, a sheet 7 after printed by theheat-generating body portion 15 a of the thermal head 15 is guided bythe sheet discharge guide face 13 b and discharged to the top of the lidbody 10 through a slit defined by the upper cover 5 of the main bodycase 2 and the lid body 10 as shown in FIG. 1.

Next, a sheet package 9 of the first embodiment of the presentdisclosure to be set in the printer unit 1 will be described withreference to FIGS. 5-14.

As shown in FIG. 5, the sheet package 9 is made up of a package material8 which is folded into a rectangular parallelepiped thin box. The sheetpackage 9 contains a plurality of sheets (recording object mediums) 7composed of, for example, A6-A7 size cut-sheet like heat sensitivepapers in a stacked condition. Users purchase sheet packages 9 that areput on sale in a box type condition shown in FIG. 5. And as shown inFIGS. 6 and 7, a lid portion 44 is opened and folded back to the rearside. An insert section 44 d of the lid portion 44 is inserted into athird slit 45 in a bottom portion 40, which will be described later soas to expose sheets 7 located on the inside. Then, the user sets thesheets together with the package material 8 in the sheet storage portion6 of the printer unit 1 and uses.

Next, the structure of the package material 8 will be described withreference to FIGS. 8 and 9. As shown in FIGS. 8 and 9, the packagematerial 8 is formed by punching out a flat thick paper. A rectangularbottom portion 40, for covering one face in a stack direction of thestacked sheets 7 is provided in the central portion of the packagematerial 8. For convenience for explanation, the lid side in a dischargedirection of the sheet 7 in the sheet package 9, that is, right side ofthe package material 8 is defined to be front side and the left side onopposite side is defined to be rear side. A side wall portion 41, whichis rectangular, and is extended from one of a pair of side end portionsof the bottom portion 40 while a rectangular side wall portion 42, isextended from the other side end portion and a rectangular side wallportion 43, is extended from the rear end portion of the bottom portion40. The side wall portion 43 receives the bottom end portion of thesheets 7 when the sheet package 9 is assembled. The heights of the sidewall portions 41-43 (width in short side direction) are all the same andlarger than the stack height of the sheets 7 stored in the sheet package9.

As shown in FIGS. 8 and 9, the lid portion 44 is extended from the frontend side of the bottom portion 40. The lid portion 44 is comprised of alid base portion 44 a, a lid side wall portion 44 b, a lid front endportion 44 c and an insertion portion 44 d. The lid base portion 44 a isformed in a rectangular shape. The lid side wall portion 44 b is formedin a rectangular shape and is extended from the lid base portion 44 a,having the same height (width in a short side direction) as the heightsof the side wall portions 41 to 43. The lid front end portion 44 c isextended from the lid side wall portion 44 b and a width thereof issmaller than that of the lid side wall portion 44 b. The insertionportion 44 d is extended from the lid front end portion 44 c and a widththereof is smaller than the lid front end portion 44 c. A pair ofinclined sides is provided at the front end of the insertion portion 44d. A shape that is formed by a combination of the bottom portion 40 andthe lid base portion 44 a is substantially the same shape as a sheet 7.

As shown in FIGS. 8 and 9, a rectangular first sheath portion 50, forcovering the sheets 7 in such a way that it opposes the bottom portion40 after assembly is extended from the side wall portion 41 of thebottom portion 40. The first sheath portion 50 has a first slit 51 inwhich the insert section 44 d of the lid portion 44 is inserted and asecond slit 52 in which an insert section 61 of a second sheath portion60 is inserted. A square cutout portion 53 for detecting thepresence/absence of a sheet 7 is provided in a side end portion on thelid base portion 44 a side of the first sheath portion 50. The printerunit 1 detects the presence/absence of a sheet 7 with the use of thecutout portion 53. In other words, the sheet package 9 is loaded on thesheet storage portion 6 of the printer unit 1 in the state shown in FIG.6, and the printer unit 1 is provided with a reflection type opticalsensor 80 (see FIGS. 3 and 4) at a position opposite to the cutoutportion 53. Thus, when any sheets 7 are present in the sheet package 9,the reflection type optical sensor detects reflection of light from thesheets 7 and if no sheet 7 is present, the reflection type opticalsensor detects reflection light from a synthetic resin which constitutesthe rear face of the lid body 10. Therefore, if as the color of thesynthetic resin which constitutes the sheet storage portion 6, a colorhaving a low reflectance ratio is set, the presence/absence of a sheetcan be easily detected.

As shown in FIG. 8, three sensor marks 46 which indicate the type andsize of sheets 7 stored in the sheet package 9 are printed on an endportion on the first sheath portion 50 side of the bottom portion 40 onthe front side (outer side) of the package material 8. These sensormarks 46 are read by a reflection type optical sensor (a sensor (notshown) that is different from the reflection type optical sensor 80),and that is provided on the printer unit 1. For example, if the sensormark 46 is printed, it is regarded as “1”, and the sensor mark 46 is notprinted, it is regarded as “0”, then the absence of a sheet and sevendifferent types of sheets 7 can be identified with the combination ofpresence or absence of the three sensor marks 46. The bottom portion 40is provided with a third slit 45 in which the insert section 44 d of afolded back lid portion 44 is to be inserted. Further, a cut-in portion54 which is cut to a predetermined length from the cutout portion 53side is provided between the side wall portion 41 and the first sheathportion 50. The cut-in portion 54 facilitates deflection of the firstsheath portion 50 when the first sheath portion 50 is pressed if thesheet package 9 is loaded on the sheet storage portion 6.

As shown in FIGS. 8 and 9, a second sheath portion 60 for fixing thefirst sheath 50 for covering the sheets 7 in such a way that it opposesthe bottom portion 40 after assembly is provided so as to extend as faras side wall portion 42 of the bottom portion 40. The width of thesecond sheath portion 60 is smaller than that of the first sheathportion 50 and the insert section 61 is formed on a side end portion ofthe second sheath portion 60. When the sheet package 9 is assembled, theinsert section 61 is inserted into the second slit 52 in the firstsheath portion 50 so as to fix the first sheath portion 50 opposing tothe bottom portion 40.

As shown in FIGS. 8 and 9, a tongue portion 70, which is rectangular, isextended from the side wall portion 43 of the bottom portion 40.Rectangular ear portions 71 and 72 are provided on both end portions inthe longitudinal direction of the tongue portion 70. When the earportions 71 and 72 are fold, they perform as sheet intrusion blockingmembers. A portion indicated with two-dot and chain line in both FIGS. 8and 9 is a portion that is subjected to fold line processing and thefold line facilitates folding of a thick paper for convenience ofassembly.

Next, a manufacturing process of the sheet package 9 will be describedwith reference to FIGS. 10 to 14. As shown in FIG. 10, the ear portions71 and 72 on both end portions in the longitudinal direction of thetongue portion 70 are folded back and the stacked sheets 7 are loaded onthe bottom portion 40. Next, as shown in FIG. 11, the tongue portion 70of the package material 8 is fold over. Next, as shown in FIG. 12, thefirst sheath portion 50 is folded in such a way that it overlaps withthe top of the tongue portion 70 and as shown in FIG. 13, the secondsheath portion 60 is folded over the first sheath portion 50. Next, theinsert section 61 of the second sheath portion 60 is inserted into thesecond slit 52 in the first sheath portion 50.

Finally, as shown in FIG. 14, the lid portion 44 is folded over thefirst sheath portion 50, the insert section 44 d of the lid portion 44is inserted into the first slit 51 in the first sheath portion 50, andthe sheet package is thus completed. Sheet packages 9 are sold in thiscondition. Because this condition allows the ear portions 71 and 72 toseek to be elastically restored within the sheet package 9, they pressagainst the surface of the stacked sheets 7.

Next, a method of using the sheet package 9 will be described withreference to FIGS. 3, 5, 6, 7, 15, 16 and 17. When a sheet package 9 isused, the lid portion 44 of the sheet package 9 in the state shown inFIG. 5 is erected as shown in FIG. 15 and folded back to the rear sidealong the line II-II in FIG. 16. Then, as shown in FIG. 7, the insertsection 44 d of the lid front end portion 44 c of the lid portion 44 isinserted into the third slit 45 of the bottom portion 40 and the lidportion 44 is fixed to the bottom portion 40. Consequently, as shown inFIG. 6, the sheet package 9 reverts to a state in which the front endportion of the sheets 7 is exposed. The sheet package 9 in this state isstored in the sheet storage portion 6 of the printer unit 1 as shown inFIG. 3. When the lid body 10 is closed, the first sheath portion 50 ofthe sheet package 9 is pressed by the pressing plate 18 and the sheetthat is located on the bottommost layer of the stacked sheets 7 ispressed against the pickup roller 12.

At this time, the reflection type optical sensor 80 that is provided onthe printer unit 1 opposes the cutout portion 53 provided in the firstsheath portion 50 of the sheet package 9 (see FIGS. 3, 4). Therefore,when any sheets 7 are present in the sheet package 9, the reflectiontype optical sensor 80 detects reflection light from a sheet 7 and whenno sheet 7 is present, it detects reflection light from a syntheticresin which constitutes the rear face of the lid body 10.

Next, an action of a sheet intrusion blocking member (ear portions 71and 72) of the present disclosure will be described with reference toFIGS. 6, 16 to 22.

When the lid portion 44 of the sheet package 9 is folded back as shownin FIGS. 6 and 16, in the sheet package 9, the ear portions 71 and 72that are folded back from both end portions of the tongue portion 70press against the surface of the sheet 7 stored in the sheet package 9as shown in FIG. 18. The pressing force of the ear portions 71 and 72 isgenerated when the ear portions 71 and 72 seek to become elasticallyrestored by means of elasticity of the package material 8. When thequantity of sheets stored in the sheet package 9 is small, the earportions 71 and 72 are elastically restored so as to press against thesurface of a sheet 7 as shown in FIG. 19. Therefore, when the lidportion 44 of the sheet package 9 is folded back, sheets 7 can beprevented from dropping out of the sheet package 9.

In circumstances such as when all sheets 7 have been pulled out from thesheet package 9 by a user, or when a user swings the sheet package 9with the opening portion 49 facing downwards with folding back the lidportion 44, all the sheets 7 might drop out from the sheet package 9. Insuch circumstances, the ear portions 71 and 72 are elastically restoredby means of the elasticity of the package 8 along the fold line as shownin FIG. 20, so that the front ends of the ear portions 71 and 72 makecontact with the bottom portion 40. In this state, if sheets 7 areinserted into the sheet package 9 through the opening portion 49 asshown in FIG. 21, the ear portions 71 and 72 are located in spacesandwiched by the bottom portion 40 (the first portion) and the firstsheath portion 50 (the second portion) as shown in FIG. 22 and the sideends of the ear portions 71 and 72 make contact with the end portions ofthe sheets 7 in an insertion direction, and the end portions of thesheets 7 are consequently unable to contact with the side wall portion43. Therefore, the sheets 7 cannot be restored to their originalpositions in the sheet package 9 as shown in FIG. 22 and consequently,part of the sheets 7 project from the sheet package 9. Thus, the droppedsheets 7 cannot be restored to their normal storage positions in thesheet package 9 through opening portion 49, thereby preventing sheets 7to which dust or dirt has adhered from being used again.

Next, a second embodiment of the sheet package 9 will be described withreference to FIGS. 23 and 24.

Because substantially every configuration of the package material 8 ofthe sheet package 9 of the second embodiment is identical to the packagematerial of the first embodiment as shown in FIG. 23, only differentportions will be described. As shown in FIG. 23, the package material 8of the sheet package 9 of the second embodiment is provided with atongue portion 70 which is rectangular. The ear portions 73 and 74 whichare rectangular, are provided in a central portion in a longitudinaldirection of the tongue portion 70 with a cut line (straight) and a foldline (two-dot and chain line). When the ear portions 73 and 74 arefolded back, they perform identical functions to those of the earportions 71 and 72 of the first embodiment. According to the secondembodiment, if the tongue portion 70 is raised and folded and the earportions 73 and 74 are folded as shown in FIG. 24, the ear portions 73and 74 press against the sheets 7, thereby producing identicaloperations and effects to those in the first embodiment.

A third embodiment of the sheet package 9 will now be described withreference to FIG. 25.

Because substantially every configuration of the package material 8 ofthe sheet package 9 of the third embodiment is identical to the packagematerial of the first embodiment as shown in FIG. 25, only differentportions will be described. Although as shown in FIG. 25, the packagematerial 8 of the sheet package 9 of the third embodiment is providedwith a tongue portion 70 which is rectangular, ear portions are notprovided on the tongue portion 70. According to the third embodiment,the ear portions 47 and 48 which is rectangular are provided on thebottom portion 40 with a cut line (straight) and a fold line (two-dotand chain line). Therefore, before the sheets 7 are loaded on the bottomportion 40, the ear portions 47 and 48 of the bottom portion 40 areraised and folded back and then sheets 7 are loaded thereon.Consequently, the ear portions 47 and 48 press the sheets 7, therebyproducing identical operations and effects to those of the firstembodiment.

Next, a fourth embodiment of the sheet package 9 will be described withreference to FIG. 26.

Because substantially every configuration of the package material 8 ofthe sheet package 9 of the fourth embodiment is identical to the packagematerial of the third embodiment as shown in FIG. 26, only differentportions will be explained. Although the package material 8 of the sheetpackage 9 of the fourth embodiment is provided with the tongue portion70 which is rectangular as shown in FIG. 26, the ear portion is notprovided on the tongue portion 70. According to the fourth embodiment,the ear portions 57 and 58 which are rectangular, are provided on thefirst sheath portion 50 with a cut line (straight) and a fold line(two-dot and chain line) provided. Therefore, sheets 7 are loaded on thebottom portion 40, and before the first sheath portion 50 is foldedback, the ear portions 57 and 58 are raised and folded back. When thefirst sheath portion 50 is folded, the ear portions 57 and 58 pressagainst the sheets 7, thereby producing identical operations and effectsto those in the first embodiment.

Next, a fifth embodiment of the sheet package 9 will be described withreference to FIG. 27. Substantially every configuration of the packagematerial 8 of the sheet package 9 of the fifth embodiment is identicalto the package material 8 of the first embodiment as shown in FIG. 8.The different point is that the boundary line 401 between the bottomportion 40 and the side wall portion 41, the boundary line 402 betweenthe bottom portion 40 and the side wall portion 42, and the boundaryline 403 between the bottom portion 40 and the side wall portion 43 areperforated.

Ordinarily, the fold line processing with half-round shape embossing isprocessed on the boundary line in the package material 8. The fold lineprocessing with half-round shape embossing is performed from the outerside to the inner side in assembling the package material 8. Theboundary line is facilitated to fold by the fold line processing. Whenthe boundary line processed with the fold line processing by embossingis fold, the embossment portion 410 is formed on the inner side of thefold line along the fold line (See FIG. 30). The boundary line 401between the bottom portion 40 and the side wall portion 41, the boundaryline 402 between the bottom portion 40 and the side wall portion 42, andthe boundary line 403 between the bottom portion 40 and the side wallportion 43 are processed with the ordinary fold line processing withhalf-round shape embossing. When each of the boundary lines 401, 402 and403 is folded, the embossment portion 410 is formed on the inner side ofthe fold line along the fold line (See FIG. 30). That is because theinner part of the fold line is compressed when the boundary line isfolded, and the inner part need the releasing portion of the compressionto bulge. Some fiber of the package material 8 is unraveled within theembossment portion, and the fiber density is slightly less than otherportions. The bottom portion 40 is situated next to the embossmentportion 410 formed on the boundary line 401. The space 411 is formedbetween the bottom portion 40 and the embossment portion 410. The sheet7 can be wedged in the space 411. The same goes for the space formedbetween the bottom portion 40 and the boundary line 402, and the spacebetween the bottom portion 40 and the boundary line 403. If the sheet iswedged in the space once, the wedged sheet may not be ejected byoperating the printer unit 1. The sheet that may be wedged is only thesheet 7 located on the bottommost layer of the stacked sheets opposingto the bottom portion 40. As described before, a face provided in thepackage material 8 to wedge the sheet 7 and the embossment portionadjacent to the face are needed for wedging the sheet 7. The sheet 7 iswedged easily if the sheet 7 contacts the face in parallel. The sheet 7can be wedged easily if the edge of the sheet 7 contacts parallel withthe linear embossment portion. In that respect, the size of the sheetstorage portion 6 in present embodiment as seen in a plan view is almostthe same as that of the sheet 7 stored in it. Because the each edge ofthe sheet 7 is regulated by the inner wall of the sheet storage portion6 or by the side wall of the package material 8, the edge of the sheet 7contacts the linear embossment portion easily in parallel with thelinear embossment portion. Since the sheet 7 located on the bottommostlayer is pressed to the bottom portion 40 by the effect of gravitation,the effect of urging the sheet 7 in a downward direction by the earportions 71 and 72 at the upstream of conveyance direction of the sheet,and the effect of urging the sheet 7 in a downward direction by theurging spring 19 at the downstream of conveyance direction of the sheet,the sheet 7 is wedged easily. Even in the bottommost sheet 7, the parturged in a downward direction is more inclined to be wedged than thepart not urged in a downward direction.

However, the sheet package 9 provides the lid base portion 44 a which isfolded back to the rear side when the sheet package 9 is loaded to thesheet storage portion 6. The length of the lid base portion 44 a inconveyance direction is approximately one-third of the length of thesheet package 9 in conveyance direction. Sine the bottom portion 40 isformed shortly for the length of the lid base portion 44 a, and the sidewalls are formed in some part of the bottom portion 40, there is no foldline parallel to the conveyance direction of the sheet and is no theembossment portion in the one-third length portion from the end of thedownstream to the upstream side in conveyance direction on the bottomface in the sheet package 9. The urging spring 19 is structured so as tourge the sheet 7 strongly in a downward direction at the end of thedownstream of conveyance direction in the sheet package 9 and urge thesheet 7 weakly as toward to the upstream. Therefore, the potential thatthe sheet 7 can be wedged due to urging the sheet 7 in a downwarddirection by the urging spring 19 at the downstream of conveyancedirection of the sheet is smaller than the potential that the sheet 7can be wedged due to urging the sheet 7 in a downward direction by theear portions 71 and 72 at the upstream of conveyance direction of thesheet.

Compared with the package material 8 processed with the ordinary foldline processing, the package material 8 in the present embodimentprovides the perforated lines on the boundary line 401 between thebottom portion 40 and the side wall portion 41, the boundary line 402between the bottom portion 40 and the side wall portion 42, and theboundary line 403 between the bottom portion 40 and the side wallportion 43, as described before. For example, as shown in FIG. 31, theperforated line 412 facilitates folding of the side wall 41 to thebottom portion 40, and the embossment portion is not formed on the innerside of the fold line folded at the boundary line processed with theperforated line. The perforated line 412 facilitates folding of the sidewalls 42 and 43 to the bottom portion 40, and the embossment portion isnot formed on the inner side of the fold line folded at the boundaryline processed with the perforated line, as the same as above. As aresult, unlike the sheet package 9 with the ordinary fold lineprocessing, the sheet package 9 in the present embodiment can preventthe sheet 7 located on the bottommost layer of the stacked sheetsopposing to the bottom portion 40 from being wedged in the boundary linebetween the bottom portion 40 and the side wall portion 41, the boundaryline between the bottom portion 40 and the side wall portion 42, or theboundary line between the bottom portion 40 and the side wall portion43. In the package material 8 in the fifth embodiment, the boundary line404 between the first sheath portion 50 and the side wall portion 41,the boundary line 405 between the second sheath portion 60 and the sidewall portion 42, and the boundary line 406 between the tongue portion 70and the side wall portion 43 are processed with the ordinary fold lineprocessing with half-round shape embossing.

In the sheet package 9 of the present embodiment, the perforated linesare provided on the boundary line 401 between the bottom portion 40 andthe side wall portion 41, the boundary line 402 between the bottomportion 40 and the side wall portion 42, and the boundary line 403between the bottom portion 40 and the side wall portion 43. Theperforated lines may be provided on only the boundary line 403 that isthe border with the bottom portion 40 opposing the ear portions 71 and72 through the sheet 7 and where the sheet 7 is urged strongly by theear portions 71 and 72 in a downward direction. On that occasion, inaddition, the perforated lines may be provided on only the portion wherethe border with the bottom portion 40 opposing the ear portions 71 and72 through the sheet 7 and that is adjacent to the ear portions 71 and72 in the boundary line 403. The perforated lines may be provided on theportion that is the end of the upstream of conveyance direction of thesheet 7 in the boundary line 402 with the bottom portion 40 opposing theear portion 71 through the sheet 7 and that is adjacent to the earportion 71 in the boundary line 402, the portion that is the end of theupstream of conveyance direction of the sheet 7 in the boundary line 401and that is adjacent to the ear portion 72 in the boundary line 401 withthe bottom portion 40 opposing the ear portion 72 through the sheet 7,and the boundary line 403.

Next, a sixth embodiment of the sheet package 9 will be described withreference to FIG. 28. The object of the sheet package 9 in the presentembodiment is to prevent the sheet 7 located on the bottommost layer ofthe stacked sheets opposing to the bottom portion 40 from being wedgedin the boundary line between the bottom portion 40 and the side wallportion 41, the boundary line between the bottom portion 40 and the sidewall portion 42, and the boundary line between the bottom portion 40 andthe side wall portion 43, as the same as the sheet package 9 in thefifth embodiment. Substantially every configuration of the packagematerial 8 of the sheet package 9 of the sixth embodiment is identicalto the package material 8 of the first embodiment as shown in FIG. 8. Asshown in FIG. 28, the different point is that the boundary line 401between the bottom portion 40 and the side wall portion 41, the boundaryline 402 between the bottom portion 40 and the side wall portion 42, andthe boundary line 403 between the bottom portion 40 and the side wallportion 43 are processed with half-cut processing on each inner side ofthe boundary line 401, 402 and 403 so that the side wall portions 41, 42and 43 can be folded easily. The half-cut processing is processing tomake incisions with the depth of half-thickness of the package material8. With the half-cut processing, the side wall portions 41, 42 and 43can be folded to the bottom portion 40 easily and the sheet 7 located onthe bottommost layer of the stacked sheets opposing to the bottomportion 40 is prevented from being wedged in the boundary line 401between the bottom portion 40 and the side wall portion 41, the boundaryline 402 between the bottom portion 40 and the side wall portion 42, andthe boundary line 403 between the bottom portion 40 and the side wallportion 43 because the boundary lines between the side wall portions 41,42 and 43 and the bottom portion 40 are folded closely to the bottomportion 40. In the package material 8 of the sixth embodiment, theboundary line 404 between the first sheath portion 50 and the side wallportion 41, the boundary line 405 between the second sheath portion 60and the side wall portion 42, and the boundary line 406 between thetongue portion 70 and the side wall portion 43 are processed with theordinary fold line processing with half-round shape embossing.

Next, a seventh embodiment of the sheet package 9 will be described withreference to FIG. 29. The object of the sheet package 9 in the presentembodiment is to prevent the sheet 7 located on the bottommost layer ofthe stacked sheets opposing to the bottom portion 40 from being wedgedin the boundary line between the bottom portion 40 and the side wallportion 41, the boundary line between the bottom portion 40 and the sidewall portion 42, and the boundary line between the bottom portion 40 andthe side wall portion 43, as the same as the sheet package 9 in thefifth embodiment. Substantially every configuration of the packagematerial 8 of the sheet package 9 of the seventh embodiment is identicalto the package material 8 of the first embodiment as shown in FIG. 8.The different point is that the pit-like indentations with predetermineddepth is provided in line on the boundary line 401 between the bottomportion 40 and the side wall portion 41, the boundary line 402 betweenthe bottom portion 40 and the side wall portion 42, and the boundaryline 403 between the bottom portion 40 and the side wall portion 43, asshown in FIG. 29. By the fold line processing with pits, the side wallportions 41, 42 and 43 can be folded to the bottom portion 40 easily andthe sheet 7 located on the bottommost layer of the stacked sheetsopposing to the bottom portion 40 is prevented from being wedged in theboundary line 401 between the bottom portion 40 and the side wallportion 41, the boundary line 402 between the bottom portion 40 and theside wall portion 42, and the boundary line 403 between the bottomportion 40 and the side wall portion 43. In the package material 8 ofthe seventh embodiment, the boundary line 404 between the first sheathportion 50 and the side wall portion 41, the boundary line 405 betweenthe second sheath portion 60 and the side wall portion 42, and theboundary line 406 between the tongue portion 70 and the side wallportion 43 are processed with the ordinary fold line processing withhalf-round shape embossing. Above described term “perforated line”,“half-cut processing” and “pit-like indentation” correspond to theindentation portion.

The present disclosure is not limited to the above-described embodimentsbut may be modified in various ways. For example, a single ear portionis permitted instead of a pair of ear portions on the right and leftsides. The shape of the ear portion is not limited to a rectangular onebut may be of any shape such as trapezoid. Although, according to theembodiments, the side wall portion 42 is extended from the bottomportion 40, the side wall portion 42 may also be extended from the firstsheath portion 50, while the second sheath portion 60 may be extendedfrom the side wall portion 42. Although according to the embodiments,the side wall portion 43 is extended from the bottom portion 40, theside wall portion 43 may also be extended from the first sheath portion50, while the tongue portion 70 may be extended from the side wallportion 43. The term “perforated line”, “half-cut processing” and“pit-like indentation” are not necessary to be provided on whole of theboundary line 401 between the 40 and the 41, the boundary line 402between the 40 and the 42, and the boundary line 403 between the 40 andthe 43. For example, they may be provided on only the portion where thesheet 7 is wedged easily and other portions may be processed with theordinary fold processing with half-round shape embossing. As portionswhere the sheet 7 is wedged easily are the boundary line between thebottom portion 40 and the side wall portion 41, the boundary betweenline the bottom portion 40 and the side wall portion 42 which opposes tofront side of the first sheath portion 50 pressed by the pressing plate18 of the printer unit 1, and the boundary line between some side wallportion and the bottom portion 40 where is adjacent to the portion urgedthe sheet 7 by ear portion, for example.

The printer unit 1 described in the above embodiment discharges thesheet 7 through the slit between the upper cover 5 of the main body case2 and the lid body 10. The printer unit 1 is available, even if the sideof the printer unit 1 is set down or the upper cover 5 of the printerunit 1 is set down, unless the slit is blocked. Needless to say, thesheet package 9 loaded in the printer unit 1 also stands or is reversedcorresponding to each occasion.

1. A sheet package comprising: stacked sheets accommodated in the sheetpackage, as printing object mediums for a printer unit and a packagematerial that covers the outer sides of the stacked sheets and having; afirst portion that is rectangular and covers a surface on one side in astacking direction of the stacked sheets; a second portion that covers asurface on another side in a stacking direction of the stacked sheetsopposite to the first portion; a third portion that is connected to boththe first portion and to the second portion for covering a side face ofthe stacked sheets in parallel to a conveyance direction of the sheets;a fourth portion that covers the side face of the stacked sheets inparallel to the conveyance direction of the sheets and that is oppositeto the third portion across the stacked sheets; a fifth portion that isconnected to one of the first portion and the second portion and thatcovers the side face of the stacked sheets on an upstream side in theconveyance direction of the sheets; an opening portion that exposes partof the sheets from the package material; and sheet intrusion blockingmembers that prevent any sheets discharged through the opening portionfrom being inserted once again through the opening portion and pressedagainst their original storage positions, the sheet intrusion blockingmembers being provided in the interior after assembly of the sheetpackage, wherein the sheet package being structured so as to be capableof being set in the printer unit together with the package material withpart of the sheets exposed.
 2. The sheet package according to claim 1,further comprising a sixth portion that is connected to the fifthportion and that overlaps with the one of the first and second portionsnot connected with the fifth portion wherein the sheet intrusionblocking members are provided on the sixth portion and block the sheetsdischarged through the opening portion from making contact once againwith the fifth portion through the opening portion.
 3. The sheet packageaccording to claim 2, wherein the sheet intrusion blocking members areear portions provided on the sixth portion and extended in a directionperpendicular to the conveyance direction of the sheet along fold linesand the ear portions are elastically restored along the fold line due toelasticity of the package material so that the front ends of the earportions are located away from the sixth portion in a space sandwichedby the first portion and the second portion in a space between thesecond portion and the stacked sheets when the fifth portion isconnected to the first portion, or in a space between the first portionand the stacked sheets when the fifth portion is connected to the secondportion whereby, side ends of the ear portion butting against the sheetsinserted to make contact with the fifth portion through the openingportion so as to prevent the sheets from making contact with the fifthportion.
 4. The sheet package according to claim 3, wherein anindentation portion is provided on an inner side of a fold line betweenthe first portion and fifth portion when the fifth portion is connectedto the first portion or, an inner side of a fold line between the secondportion and fifth portion when the fifth portion is connected to thesecond portion.
 5. The sheet package according to claim 4, wherein theindentation portion is formed with one of perforations, half-cuts orpit-like indentation
 6. The sheet package according to claim 1, whereinthe sheet intrusion blocking members are provided on the first portionin such a way that the sheets discharged through the opening portion areprevented from making contact once again with the fifth portion throughthe opening portion.
 7. The sheet package according to claim 6, whereinthe sheet intrusion blocking members are ear portions provided on thefirst portion and extended in a direction perpendicular to theconveyance direction of the sheet along a fold line; and the earportions are elastically restored along the fold line due to elasticityof the package material so that the front ends of the ear portions arelocated away from the first portion in a space sandwiched by the firstportion and the second portion or in a space between the first portionand the stacked sheets whereby, side ends of the ear portion buttingagainst the sheets inserted to make contact with the fifth portionthrough the opening portion so as to prevent the sheets from makingcontact with the fifth portion.
 8. The sheet package according to claim7, wherein an indentation portion is provided respectively on an innerside of a fold line between the second portion and third portion, aninner side of a fold line between the second portion and fourth portionwhen the fourth portion is connected to the second portion, and an innerside of a fold line between the second portion and fifth portion whenthe fifth portion is connected to the second portion.
 9. The sheetpackage according to claim 8, wherein the indentation portion is formedwith one of perforations, half-cuts or pit-like indentation.
 10. Thesheet package according to claim 1, wherein the sheet intrusion blockingmembers are ear portions provided on the first portion and extended in adirection perpendicular to the conveyance direction of the sheet along afold line; and the ear portions are elastically restored along the foldline due to elasticity of the package material so that the front ends ofthe ear portions are located away from the first portion in a spacesandwiched by the first portion and the second portion or in a spacebetween the first portion and the stacked sheets whereby, side ends ofthe ear portion butting against the sheets inserted to make contact withthe fifth portion through the opening portion so as to prevent thesheets from making contact with the fifth portion.
 11. The sheet packageaccording to claim 10, wherein an indentation portion is providedrespectively on an inner side of a fold line between the second portionand third portion, an inner side of a fold line between the secondportion and fourth portion when the fourth portion is connected to thesecond portion, and an inner side of a fold line between the secondportion and fifth portion when the fifth portion is connected to thesecond portion.
 12. The sheet package according to claim 11, wherein theindentation portion is formed with one of perforations, half-cuts orpit-like indentation.
 13. A sheet package comprising: a package materialthat covers the outer sides of stacked sheets and having; a firstportion that is rectangular and covers a surface on one side in astacking direction of the stacked sheets; a second portion that covers asurface on another side in a stacking direction of the stacked sheetsopposite to the first portion; a third portion that is connected to boththe first portion and to the second portion for covering a side face ofthe stacked sheets in parallel to a conveyance direction of the sheets;a fourth portion that covers the side face of the stacked sheets inparallel to the conveyance direction of the sheets and that is oppositeto the third portion; a fifth portion that is connected to the firstportion or the second portion and that covers the side face of thestacked sheets on an upstream side in the conveyance direction of thesheets; an opening portion that exposes part of the sheets from thepackage material; and sheet intrusion blocking members that prevent thesheets discharged through the opening portion from being inserted onceagain through the opening portion and pressed against their originalstorage positions, the sheet intrusion blocking members being providedin the interior after assembly of the sheet package, wherein the sheetpackage being structured so as to be capable of being set in the printerunit together with the package material with part of the sheets exposed.